With the surge in consumer demand for personalized and high-quality services, subscription e-commerce has become a leading business model, enhancing customer loyalty and reducing marketing expenditures while adapting to market dynamics. Despite extensive empirical research, quantitative studies focusing on optimizing product combinations within subscription services are relatively scarce. This study introduces an innovative optimization model that addresses this gap, emphasizing the strategic introduction of new products in subscription boxes to boost customer interest and satisfaction. Utilizing mathematical programming, our model aims to minimize costs while ensuring that the product combinations in each subscription box meet minimum customer utility thresholds, considering key variables such as new product integration, lead time, and inventory safety. Numerical simulations confirm the effectiveness of the model, providing subscription businesses with tangible data to guide decision-making. This research not only contributes theoretical insights to the field of subscription e-commerce but also offers strategic guidance for industry practices, highlighting the role of the optimization model in enhancing customer experience, strengthening business competitiveness, and promoting industry innovation and sustainable growth.